glFlush -- force execution of GL commands in finite time
void glFlush(void void)
Different GL implementations buffer commands in several different locations,
including network buffers and the graphics accelerator itself. glFlush
empties all of these buffers, causing all issued commands to be executed as
quickly as they are accepted by the actual rendering engine. Though this
execution may not be completed in any particular time period, it does complete
in finite time.
Because any GL program might be executed over a network, or on an accelerator
that buffers commands, all programs should call glFlush whenever they
count on having all of their previously issued commands completed. For example,
call glFlush before waiting for user input that depends on the generated
glFlush can return at any time. It does not wait until the execution of
all previously issued GL commands is complete.
GL_INVALID_OPERATION is generated if glFlush is called
between a call to glBegin and the
corresponding call to glEnd.
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© 1995 Uwe Behrens. All rights reserved.